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January 18, 2014 5:37 PM   Subscribe

Two pounds of dry ice in the kitchen sink.
posted by griphus (68 comments total) 15 users marked this as a favorite

 
Very neat! Wish I could get dry ice.
posted by turbid dahlia at 5:46 PM on January 18


That is worse faek R-r-r-russian accent I have heard in long tiem.
posted by laconic skeuomorph at 5:46 PM on January 18 [5 favorites]


While this is fairly elementary as far as "experiments" go, yeah, it's still awesome. They got the tone exactly right too -- no over production, a very brief logo at the start, no posing, no telling us ahead of time for three minutes how awesome it's going to be, just two excited guys goofing around doing fun stuff!

(I do wonder how this guy got over 1M subscribers though. Yikes!)
posted by JHarris at 5:47 PM on January 18


NO DON'T LIE DOWN THAT IS A VERY BAD IDEA CO2 IS HEAVIER THAN AIR ACK ACK ACK
posted by KathrynT at 5:55 PM on January 18 [34 favorites]


Yeah, the lying down in it kind of freaked me out. But fun! With science!
posted by gingerbeer at 5:56 PM on January 18


Wish I could get dry ice.

Check with your local ice cream store. Baskin Robbins was always my go-to for dry ice when I did this kind of "experiment" as a kid.
posted by JimInLoganSquare at 5:56 PM on January 18 [1 favorite]


After all the crap we have collectively been through lately, I can't tell you how much we needed a dry ice video, a refrigerator manual, a 1950's robot and Andy Griffith, Space Junkman. Thank you, Metafilter, for saving my faith in humanity.
posted by oneswellfoop at 6:00 PM on January 18 [27 favorites]


A few posts down someone mentions being seeing Iron Maiden in '85. Seeing the guy lay on the floor (and wondering if his was going to pass out), reminded me of seeing Maiden myself in '85 - front row center at Merriwhether Post Pavilion (got there right before the show and they released some more tickets that had been reserved). When they played Rime of the Ancient Mariner, they ran the fog machines wide open, and there were security guards kneeling down in front of the stage who got completely covered by a 2 foot layer of fog that rolled off the edge of the stage.
posted by 445supermag at 6:01 PM on January 18 [4 favorites]


Yeah, the lying down in it kind of freaked me out. But fun! With science!

I think laying down in it for an extended period would be bad, since the CO2 and water vapor is displacing the rest of the air, but it's not outright poisonous like CO, carbon monoxide, is. The effect would basically be like holding your breath.
posted by JHarris at 6:01 PM on January 18


Well, yes, exactly. It displaces the oxygen you need.
posted by gingerbeer at 6:03 PM on January 18 [1 favorite]


That's a ton of fun. Thanks for the link!
posted by brundlefly at 6:10 PM on January 18


My sister worked at Baskin Robbins, and one day, she walked into the bedroom with a glass of red Kool-Aid that had a chunk of dry ice in it, saying, "drink thissss."

Later on, I worked at a dinner theater and we did Dracula. In the kitchen, we boiled water in a stock pot. When Dracula was doing something sneaky, putting his moves on Elizabeth, we had a big garbage pail full of dry ice, with holes cut in the side and duct tubing going into it and then feeding out toward the stage. Hooked up to one end was a hair dryer.

At the right time, my stage manager would rush onto backstage carrying a pot of boiling water. I would lift up the cover, he would dump it into the trash can, and I would slap down the lid. Another stagehand would hit the switch on the hair dryer.

Smoke would pour out onto the stage and creep over the edge. Eery Dracula music would play. And that was our special effects.
posted by Marie Mon Dieu at 6:11 PM on January 18 [14 favorites]


Actually, CO2 is toxic - but you'll suffocate before the poison gets you.
posted by nickmark at 6:12 PM on January 18 [1 favorite]


That is worse faek R-r-r-russian accent I have heard in long tiem.

You're right, Taras Kulakov is actually Czech.
posted by griphus at 6:14 PM on January 18 [4 favorites]


(Or so Internet Rumor says. The accent is hammed up, but it's not fake.)
posted by griphus at 6:15 PM on January 18


We used to get big shipments of chemicals at work, some of which were packed in bricks of dry ice. I thought it was such a waste that the receiving guys were throwing away pounds and pounds of the stuff, so I rummaged through the dumpster and grabbed a bunch of it.

Some of it went into every toilet and urinal in the men's bathroom.

Some of it went into the bottle experiment. Take a plastic bottle, preferably one of those calistoga water bottles, and put in maybe 1/2c water. Then add a good chunk of dry ice. Compress the bottle a little to give you some time to breath and then tighten the cap down all the way. Throw the thing as far away as you can and then wait.

We waited... Waited... Geez, maybe we didn't add enough dry ice? Then BOOM! It was like a cannon going off.

My buddy took a whole bunch of the stuff, probably 20lbs, and gave it to his nephew to throw in the pool.

Yeah, dry ice is fun.
posted by cman at 6:19 PM on January 18 [2 favorites]


Actually, CO2 is toxic - but you'll suffocate before the poison gets you.

CO2 is an asphyxiant gas. It is not classified as toxic.
We are breathing it in and out with every breath. In large concentrations it will kill you in the same way a pillow will. Or water.
posted by weapons-grade pandemonium at 6:20 PM on January 18 [9 favorites]


Taras Kulakov is actually Czech.
He does *not* sound Czech--at all. There's a very identifiable Czech accent, and this is not it.
posted by yellowcandy at 6:25 PM on January 18 [1 favorite]


Then I rescind half my comment.
posted by griphus at 6:31 PM on January 18


I've always thought of Omaha Steaks as a mail order dry ice store that threw in some meat as a bonus.

Or you could find a local source here.
posted by Marky at 6:39 PM on January 18 [5 favorites]


Is oh-kay, greefus. Reely.
posted by laconic skeuomorph at 6:40 PM on January 18 [3 favorites]


Shoot, you can get dry ice in the grocery stores around here. Publix has it up near the front (or they used to, anyway).

In a fit of rage one summer, I bought a block of it and hung it up over a bug light out in the back yard one night, hoping to fool the mosquitoes into moving towards it en masse. It worked, sort of. There certainly were hundreds and hundreds of dead mosquitoes in the lamp by morning. No discernible dent in the local population though. I threw a chunk of it into a bowl of warm water to amuse the kids and myself, so the effort wasn't totally wasted.
posted by jquinby at 6:43 PM on January 18 [2 favorites]


I thought mosquitoes were attracted to warm CO2?
posted by nevercalm at 6:45 PM on January 18


Years ago there used to be a hoity-toity restaurant/bar in Vancouver that served killer martinis and a dessert called 'strawberries on a cloud' which consisted of strawberries dipped in dark chocolate on a dish of ice and dry ice. The cloud effect was really quite impressive, especially after a couple of martinis.
posted by islander at 6:47 PM on January 18


I never said it was a great idea.
posted by jquinby at 6:49 PM on January 18 [9 favorites]


Whatever nationality is known for having a self-preservation instinct? That's the one he isn't.
posted by delfin at 6:55 PM on January 18 [1 favorite]


Fun fact: you can use dry ice to make carbonated fruit.
posted by feckless fecal fear mongering at 7:01 PM on January 18 [7 favorites]


How much air is actually being displaced by the CO2? According to Wikipedia CO2 has a density of about 2kg/m^3 at 0c. They were using two pounds, which is close enough to a kilogram for our purposes. Standard kitchen cabinets are 60cm (about two feet) wide, and their kitchen floor seems to be about 2.5 by 3 cabinets, which gives an area of 1.5 meters by 1.8 meters = 2.7 square meters. So all the CO2 could have displaced all the air in a layer .5/2.7 meters deep, assuming no mixing: that's only eighteen and a half centimeters (7.3 inches) deep.

But that assumes: a) no mixing; b) all the CO2 evaporating; c) all the CO2 being in their open-ish kitchen. All these assumptions seem doubtful. I would expect that the CO2 displaced only a small fraction of the air, and lying on these guys' kitchen floor was no more dangerous than would be expected.
posted by Joe in Australia at 7:05 PM on January 18 [5 favorites]


Many moons ago I was a tour guide at Universal Studios in Hollywood. At the horror part of the tour we talked about fog. The low lying stuff that flowed over edges and clung to the floor was dry ice. But the thick fog that floated and filled the air was from a fog machine using an oil or glycol based solution. I always enjoyed filling the room and then walking though doing my best mummy, wolfman or Frankenstein imitation...
posted by jim in austin at 7:07 PM on January 18


That is worse faek R-r-r-russian accent I have heard in long tiem.

I think he's FPSRussia's nerdy cousin.
posted by cosmic.osmo at 7:22 PM on January 18 [1 favorite]


In some theatrical settings, it's liquid nitrogen instead of frozen CO2. Phantom, when it was here, used that method.
posted by feckless fecal fear mongering at 7:22 PM on January 18 [1 favorite]


MetaFilter: I never said it was a great idea.
posted by ricochet biscuit at 7:23 PM on January 18 [6 favorites]


So what happens when you throw dry ice in a boiling pot of water on a freezing day?
posted by arcticseal at 7:41 PM on January 18 [1 favorite]


An earth shattering kaboom
posted by The Whelk at 7:44 PM on January 18 [4 favorites]


That exuberant Russian accent is overdone, but it reminds me of a fellow I met when I was 18. I had gotten my first apartment, and across the back alley lived a Russian grad student. We'd help each other fix our POS cars once in a while and shoot the shit, and one day he came over to share some Russian moonshine from back home and play cribbage. I couldn't hardly drink it at first, but... it got easier as the night wore on. We stayed up until well into the small hours, noses fully candied up, drunk as hell off that paint thinner he brought over.

I was fucking wasted, and he had way more than me.

Next morning. 8 am or so, he's pounding on my door. In a bleary haze I open it, and he bursts in - "that stuff we drink last night ? Garbage. We use it to start the tractor back home. Now, I bring good stuff. Also, you like eggs ? Chickens need to swim." - in that thick Russian accent he had.

Fucker.
posted by Pogo_Fuzzybutt at 7:46 PM on January 18 [14 favorites]


I still have a half-bottle of the slivovice my grandpa brought back from the Czech Republic in the 90s. Whoo boy, Pogo...
posted by notsnot at 8:00 PM on January 18


"But that assumes: a) no mixing; b) all the CO2 evaporating; c) all the CO2 being in their open-ish kitchen. All these assumptions seem doubtful. I would expect that the CO2 displaced only a small fraction of the air, and lying on these guys' kitchen floor was no more dangerous than would be expected."

Yeah, but this video is dangerously deceptive in that in a smaller, enclosed space you really could displace enough oxygen to cause asphyxiation.

However, the body's breathing reflex (whatever it's actually called — I'm referring to what you increasingly feel as you hold your breath) is triggered not by a lack of oxygen, but by the buildup of carbon dioxide.

With some other asphyxiating gases, such as nitrogen or methane, you don't realize that you're asphyxiating because that reflex isn't triggered, you don't know anything is wrong, and so your judgment is progressively impaired until you pass out and then eventually asphyxiate and die.

In the case of carbon dioxide, you'll experience that reflex immediately and you would then know that something's wrong and hopefully get out where you can breathe some oxygen.

Carbon monoxide, as I think most here know (so I'm writing it for hypothetical others) is toxic because the red blood cells that normally carry oxygen will preferentially bind carbon monoxide instead. This is bad in numerous ways. Asphyxiation by CO2, for example, will make someone's skin bluish, because of the lack of oxygen bound to the hemoglobin. Death from CO poisoning will turn their skin bright red, because the hemoglobin bound to CO turns a bright red.

"In a fit of rage one summer, I bought a block of it and hung it up over a bug light out in the back yard one night, hoping to fool the mosquitoes into moving towards it en masse."

Bedbugs are also attracted to carbon dioxide, they'll come out of the bedding when they sense the CO2. So you can make an effective bedbug diagnostic trap from a few inexpensive materials and dry ice.
posted by Ivan Fyodorovich at 8:07 PM on January 18 [3 favorites]


Seconding Marky's Omaha Steaks comment. I always thought the three best things about getting Omaha Steaks were, in order:

1. Dry ice in the toilet! Yay!
2. Awesome cooler! (seriously, they last forever and keep (real!) ice frozen all day, and baked potatoes hot all day as well)
3. Oh yeah, meat!
posted by Curious Artificer at 8:30 PM on January 18 [4 favorites]


Our lighting tech guy built a fog machine backstage in minutes using a lightbulb-socketed heating element and rosin soldering flux, both from a nearby hardware store. The ceramic heating cone was positioned pointing up, with a dollop of flux in it. Turned on, it put out a light magical fog, that filled the space and made the light-beams glow.

Everyone was impressed, except for that one lady in the third row, that started coughing conspicuously and left the theater.
posted by StickyCarpet at 8:33 PM on January 18


When I was a kid, every Halloween we'd do something like this. My mom found a 5-gallon ceramic crock somewhere, which had a spigot at the bottom. A&W used to sell root beer syrup in a bottle, and my mom would mix up a batch, a couple gallons, and put it in the crock. Then she'd add a couple pound block of dry ice that she bought from a local dairy. Like this video, it would make a cloud of fog that flowed over the top of the crock and looked really awesome.

She was always careful; we'd put it out on the deck, so that there wasn't any danger from the CO2.

It usually took an hour or two for the root beer to get carbonated that way.
posted by Chocolate Pickle at 8:52 PM on January 18 [2 favorites]


Man I really wish there was a place to buy retail quantities here; the local dry ice place has a 50 pound minimum order.
posted by Mitheral at 9:24 PM on January 18


Maybe some you have heard about the Swedish Lucia tradition on December 13? In essence, a girl draped in white and with candles in her hair sings Christmas carols along with a big entourage. At the age of 14 or so, I took part in my school's celebration as a "stjärngosse" (starboy), which was the only role boys could have. This is what a starboy looks like, with a stick with a star in the hand and a white paper cone on the head.

This is all standard procedure, but my school also had the local tradition that us starboys should do something funny with those cones. Some guys made them very tall, someone made his very low and wide, and another one wrapped his in blinking Christmas lights. To make mine special, I took a normal cone and just cut a little hole at the tip. Inside it, I had a block of styrofoam with a plastic bottle mounted on top. Just before we made our entrance, I filled the bottle with hot water and dropped in a few chunks of dry ice. As we paced in, singing praise to St. Lucia, thick white smoke was bellowing out from my cone.

Then a friend and I had to sing a verse on our own, and our puberty voices failed us badly. We barely managed to grunt our two lines about the Christmas lights and the Christmas pig, but I didn't care all that much. The smoke worked as planned, and to me that was all that mattered.
posted by Herr Zebrurka at 9:39 PM on January 18 [10 favorites]


Oh wow, this brings back memories. My dad was a scientist at a big research facility, and whenever he worked with dry ice or liquid nitrogen he would bring home the surplus to entertain his kids.

With liquid nitrogen, would pick flowers from the garden, freeze them, offer them to mum with a flourish and then look shocked when they crumbled into tiny shards. One time we froze a banana and smashed it with a hammer. When you're a kid, very few things are funnier than a smashed banana, except perhaps your dad standing there with rubber gloves and kitchen tongs, pretending to be bereft at its demise. ("Oh no, what happened? It's broken! I was going to have that on my cereal tomorrow!). When we finally ran out of things to freeze, Dad would pour the remaining liquid nitrogen down the stairs while and I would run up and down in the spooky "mountain mist".

Dry ice was even better. We'd put small chunks of it in balloons, seal the ends, stand well back and take bets on which one would pop first. We did the "chunk of dry ice in a warm sink" trick, but that was just the beginning. Those guys in the video are amateurs! You want to really cause mayhem and/or annoy your mother? Add dish soap. Add lots of dish soap. Let's just say the kitchen floor got very, erm, clean that night.
posted by embrangled at 9:40 PM on January 18 [8 favorites]


JHarris: Yeah, the lying down in it kind of freaked me out. But fun! With science!

I think laying down in it for an extended period would be bad, since the CO2 and water vapor is displacing the rest of the air, but it's not outright poisonous like CO, carbon monoxide, is. The effect would basically be like holding your breath.

I think you're underestimating how lethal slight increases in CO2 can be.

And CO2 is absolutely poisonous. That's why your body must exhale it. (Related: uric acid is not good to drink.)
posted by IAmBroom at 10:25 PM on January 18 [1 favorite]


I work with guys from Brazil, and this guy's accent (and sense of fun + fuck danger) is veeeeeery similar.
posted by davejay at 10:37 PM on January 18


Not very relevant to the danger of asphyxiation, but note that the visible white clouds rolling off the pot are not CO2: it's moisture in the air suddenly getting hit with the cold CO2 and condensing. If you are going to mess around with CO2 or LN2 like this, do it on a humid day - you'll get more impressive results.
posted by Dr Dracator at 10:50 PM on January 18


He was hacking the ice with a knife, a nice expensive looking knife. From what I could see of the knife, it had a full tang. I would have killed him if that was my knife.
posted by JujuB at 10:56 PM on January 18 [3 favorites]


Man I really wish there was a place to buy retail quantities here

All (or nearly all) of the Walmarts near me have a locked cooler at the front of the store, where thy will sell it to you by the pound. It has a big "Dry Ice" sign on it.
posted by LEGO Damashii at 11:02 PM on January 18


OH MY GOD I AM IN LOVE WITH THIS GUY
posted by jake at 12:06 AM on January 19


For his next trick, he's going to put a free AOL-DVD in the microwave!
posted by happyroach at 12:51 AM on January 19


And CO2 is absolutely poisonous. That's why your body must exhale it.

I don't think that's what poisonous means. The problem with CO2 is that you'll asphyxiate, not that you'll be poisoned. Water isn't poisonous but you'll still drown if you try to breathe it.
posted by Justinian at 12:59 AM on January 19


He does *not* sound Czech--at all. There's a very identifiable Czech accent, and this is not it.

Not saying you're wrong -- but there's been a Russian émigré community in the Czech Republic for almost a century.
posted by dhartung at 1:34 AM on January 19 [1 favorite]


"I don't think that's what poisonous means. The problem with CO2 is that you'll asphyxiate, not that you'll be poisoned. Water isn't poisonous but you'll still drown if you try to breathe it."

These distinctions aren't unambiguous. At higher than normal partial pressures, oxygen, carbon dioxide, and nitrogen all will cause various metabolic problems that have toxic effects. And, of course, an excess of water will also cause such problems due to electrolyte imbalance and therefore osmotic transfer of excessive water into cells.

All of these can be considered intoxication.

I'm curious, though, whether IAmBroom will agree that oxygen is toxic.

At normal partial pressures, all three of these gases are not toxic in these senses. Yes, we exhale carbon dioxide, but we also inhale it. The reflex caused by holding your breath is triggered when the carbon dioxide in the lungs exceeds a certain threshold. But the main reason we have to exhale it is not because sitting there it's damaging, it's to get it out of the way so more can be eliminated (as well as making way for more oxygen uptake). Yeah, the CO2 has to be eliminated and not eliminating it would mean that it would build up from wherever it's blocked backwards, and that would be bad. But that's not really what we mean when we talk about "toxicity", usually.

More to the point, breathing pure carbon dioxide is going to asphyxiate you long before it does anything else. In fact, at normal partial pressure, it won't do anything else, if even that makes sense, and it doesn't.

And uric acid isn't toxic, either. It's only a problem as the blood concentration reaches the point where it starts to crystallize. But uric acid in the blood serves some purposes. So all else equal, ingesting uric acid (from your urine or otherwise) is not in itself toxic. In excess it is. But then many things in excess, including water, are.

The contrast with carbon monoxide makes sense because while we can tolerate breathing small amounts of carbon monoxide, it's pretty bad because its presence actively disrupts respiration, not just in displacing oxygen in the lungs, but by preferentially binding to the hemoglobin. That's really a much stronger sense of the word toxic, like cyanide is "toxic".
posted by Ivan Fyodorovich at 1:43 AM on January 19 [2 favorites]


Some young men go to the casino when they turn 18, others buy porn and cigars.

The moment I turned 18 I purchased 5 pounds of dry ice at the fish department of my local 24-hr Albertson's. (In the state of Washington you have to be 18 to buy dry ice.) My friends and I walked out of that store at midnight and immediately put it to work making dry ice bombs.

PROTIP 1: crush the dry ice by smashing the brown paper bag in which it was provided against the sidewalk repeatedly

PROTIP 2: pour this dry ice into your bomb bottle.

PROTIP 3: since you have recently consumed the contents of said bottle, pee in the bottle (instead of using water at ambient January temperature) to expedite explosion.
posted by tetracycline at 2:20 AM on January 19


...but it's not outright poisonous like CO, carbon monoxide, is.

Here we go again. It is poisonous, and in a somewhat similar way to CO. CO2 kills you quickly in concentrations of 10% or more not by displacing oxygen in the air you're breathing - the other 90% can be O2, and you'll still die - it kills you by displacing the O2 in your blood.

I laid it all out in this comment a few moths ago. Don't do what that guy did, especially if you're alone.
posted by Kirth Gerson at 4:11 AM on January 19 [4 favorites]


What is the hypothesis? Where is the control? This is not an experiment - that is playing.

You'd think that putting dry ice and water in a 2L soda bottle and throwing it into a pool would be a good idea to get a cool plume. It isn't So you'd think that weighting the bottle down with gravel first would be better. According to MeFi's own Crazy Uncle Joe, it creates grape shot.

Last year for Steve Day, I decided to do something nice for my cow-orkers and ordered up a case of mint chocolate chip It's Its1.

It was packed in dry ice, which was an opportunity to play with it with boiling water from the coffee maker (you get a much better reaction with a greater ΔT) and a violet laser pointer (pro-tip: when you're putting boiling water into a pint glass, put in a spoon to act as a heat sink and avoid shattering the glass).

1And I inadvertently alienated a large number of them (but I learned a lot about them): the woman who is lactose intolerant, the woman with celiac disease, the man who won't eat mint ice cream, the man who gets tachycardia from chocolate, the woman who won't touch an oatmeal cookie...
posted by plinth at 6:40 AM on January 19 [1 favorite]


"...it kills you by displacing the O2 in your blood."

You're right. I wasn't thinking about that, but of course that would have to happen. I still want to say that it's not like carbon monoxide poisoning, but you're right that it's not totally different, either. In both cases, respiration is actively disrupted, which is how I characterized CO poisoning.

For others reading along, what's happening is that the gas exchange in the lungs between the blood and the air, where we take in oxygen and dump carbon dioxide, depends upon there being less carbon dioxide in the air in the lungs than in the blood and the reverse in the case of oxygen. When this is true, the CO2 naturally moves in that direction while O2 moves oppositely.

But as the CO2 amount in the air, which is normally very low, moves upward, that increase proportionately reduces the rate of that transfer because the transfer relies upon the gradient of that difference, and the gradient has been reduced. There's still plenty of oxygen in the air to breathe, but that oxygen is not moving into the blood from the air and the carbon dioxide is not moving into the air from the blood.

The carbon dioxide isn't being taken in and then replacing the oxygen in the blood, as in the case of carbon monoxide poisoning, but as the carbon dioxide already in the blood has nowhere to go and the oxygen in the air doesn't move into the bloodstream, the effect is that the blood concentration of CO2 increases proportionately as the body's aerobic metabolism continues, and so you can think of it that way. It is, as Kirth Gerson says, displacing the oxygen in your blood, like riders who refuse to get off the roller-coaster ride displace new riders, even when there's still plenty of prospective riders available.

I still think, though, that because of the CO2 reflex, the experience of CO2 intoxication is different from asphyxiation due to displaced oxygen or CO poisoning because while all will have the same oxygen deprivation symptoms, CO2 intoxication will additionally have that "needing to breathe" reflex.

So Joe in Australia's calculations are very misleading, because all it would take for intoxication would be for the CO2 portion of the air (near the floor) to begin to approach the O2 portion of the air (near the floor), you don't remotely need to displace all the air in a volume (even a limited volume such as near the floor) with CO2, or to remove the O2 from the air by displacement.

Put another way, normally if you discharge CO2 into the air and it's mixed, it's going to displace proportionately the other gases in the air. Air is mostly nitrogen with some oxygen, so doing this will reduce both the nitrogen and the oxygen, which has been replaced by carbon dioxide. But even if you managed to replace only the nitrogen with carbon dioxide, keeping the oxygen amount constant, there'd still be carbon dioxide poisoning because respiration depends upon the gradient between the O2/CO2 in the air and the O2/CO2 in the blood.
posted by Ivan Fyodorovich at 6:48 AM on January 19 [3 favorites]


I worked at a stage equipment rental shop for a while out of college. Some of the things we rented were dry ice foggers. These are the things that legit stage productions use when they want fog that hangs on the ground. What always amazed me was just how close to the "basket in a sink" they were. There were two types:

The first one (the smaller of the two) was a roughly a 2' black plastic cube with a hole in the side. In the bottom was a hot water heater element. It also had a wire basket on a lever. Fill with water, let it heat, put dry ice in basket, push lever into "down position," FOG.

The second one was super cool, and had some serious output potential. It was the size of a medium trash can. Still had water heating elements in the bottom, but this time there was a big pump that pushed the heated water up over the dry ice that was sitting in a basket up near the top. The resulting fog was blown out with some powerful fans. Everything was insulated and sealed for maximum fog-making potential. Took 2-3 separate 20A circuits to run as well (fine for a purpose-built theater, but not so good for a school or church or other improvised space!)

With a little bit of know-how I can't imagine it'd be particularly tough to make either type...
posted by Wulfhere at 8:09 AM on January 19


Shortened version of my personal dry ice story, copied from elsewhere...:

My ensemble once performed Bach’s coffee cantata in a staged version together with an intermezzo by Giuseppe Orlandini in the beautiful Kungssalen of Läckö Castle upon Lake Vänern in Sweden. After the cantata, there was an intermission where the public was able to get a cup of real coffee. The intermission was announced by an actor in a classical jester’s costume, carrying an oversize coffee cup filled with dry ice that emitted some suggestive steam.

We had been playing this programme about ten times, when one day the jester-actor entered on cue, but instead of the steam, his cup was menacingly slowly and steadily overflowing with an enormous mass of pale-brown, glistening five-inch-large bubbles. Sections of the slimy trail soon splashed down on the floor behind him. The period-costume-clad and authentically bewigged orchestra, strategically placed on stage facing the audience, collectively collapsed in laughter, while our jester-actor turned around in dismay and lost his speech. The whole performance made an impression of a well-rehearsed and impeccably performed comedy sketch.

Afterwards we learned that he had tried to add verisimilitude to his steam by pouring some coffee from his thermos on top of the content of his cup – for the smell, as he said. Without even looking, he had then entered the stage...
posted by Namlit at 9:10 AM on January 19 [1 favorite]


In the case of carbon dioxide, you'll experience that reflex immediately and you would then know that something's wrong and hopefully get out where you can breathe some oxygen.

Unless you have a somewhat-slowly increasing concentration of CO2 in which case the reflex won't trigger and you'll die quite happily once the CO2 concentration is high enough. Millions of lab animals are humanely killed like this every day. Dry ice in big enough quantities really actually is dangerous because of this (I had to have a safety lecture before I was allowed to take 5 kg or more in my car for example).

Not to mention being like minus eighty something degrees C cold in both solid and vapour phase which can give a pretty nasty freezer burn.
posted by shelleycat at 9:22 AM on January 19


I want to recreate this experiment in my apartment right now. I've got Zep's "No Quarter" cued up, and I think I can scare up a laser pointer for the light show.
posted by the sobsister at 9:33 AM on January 19


"Unless you have a somewhat-slowly increasing concentration of CO2 in which case the reflex won't trigger and you'll die quite happily once the CO2 concentration is high enough. Millions of lab animals are humanely killed like this every day."

You've got it backward, I think. The goal for euthanasia is rapid CO2 intoxication, which causes rapid unconsciousness and then death. One source I just looked at recommended a flow rate of around 20% of the air volume replaced by CO2 per minute.

If you look at the Wikipedia page for hypercapnia, it shows that while a 5-6/5% of CO2 in inspired air causes the strong respiratory stimulus reflex in humans, at just 7% that's swamped by the decline of cognitive function. The recommendation I just mentioned reaches three times that within one minute. So, unconsciousness happens before a breathing panic really takes hold.

Slowly increasing the CO2 levels will do the opposite, more time will be spent in the heightened respiration reflex stage, alerting a human that something is wrong.
posted by Ivan Fyodorovich at 10:23 AM on January 19


My ten-year old just--as in minutes ago--learned to do this experiment (mixing baking soda and vinegar and pouring the resulting CO2 onto candles to extinguish the flame) for a school presentation and we are both super, super bummed she can't do this instead.
posted by looli at 2:19 PM on January 19


I don't have it backwards. You need to start with no/low CO2 and increase the flow at a rate slow enough so it doesn't trigger the reflex. Start with a lot of CO2 or increase too fast and the animal reacts and suffers. Go slow enough and it becomes dozy before the reaction kicks in and it just goes to sleep (forever). The rate needed isn't all that slow to be sure, which is why I said somewhat-slow originally, but overall the technique is pretty well tested and understood and used daily all over the world. It's the same reflex in humans which is why lab workers dealing with decent amounts of solid CO2 in enclosed spaces need proper training, which I have had.
posted by shelleycat at 12:03 PM on January 21


You know, I don't actually try to derail threads.
posted by JHarris at 12:24 PM on January 21


I don't think starting a discussion of the toxicity of CO2 in a thread about a video where somebody immerses themselves in a cloud of the stuff is really a derail. Even if it is, if it raises awareness of the hazard, I say it's good.
posted by Kirth Gerson at 12:29 PM on January 21 [2 favorites]


"The rate needed isn't all that slow to be sure, which is why I said somewhat-slow originally, but overall the technique is pretty well tested and understood and used daily all over the world."

I appreciate that you've had CO2 lab training, but you're implying that this is equivalent to training and experience in euthanizing animals, which it's not. Additionally, you're mistaken about CO2 euthanasia of animals, there is considerable disagreement about preferred methods and welfare considerations.

Having reviewed some of the literature, I think that you're confusing the dyspnea respiration reflex caused by increased blood CO2 levels, and distress caused by high levels of CO2 that are the result of acidification and consequent edema in the airways and especially the lungs, which causes a different kind of "drowning" response.

Avoiding the latter distress is the rationale for using lower concentrations of CO2, even though the time to unconsciousness and death is increased.

However, all increases in blood CO2 levels will cause the increased respiration effect and studies of human exposure all show that humans report discomfort, similar to what one feels when holding one's breath, as soon as blood CO2 levels begin to increase, beginning from only a few percent CO2 concentrations of inspired air.

I could find absolutely no literature supporting your claim that a gradual increase in CO2 level avoids this response and, indeed, it's very difficult to see why the body's CO2 monitoring would work this way for humans, as our respiration is dependent upon absolute and not relative levels of O2/CO2 in the blood. We're not going to acclimatize to increased blood CO2 levels because that is essentially the same as reduced aerobic metabolism regardless of environment and exertion.

In the US, the guidelines for animal euthanasia are broadly determined by the American Veterinary Medical Association and its 2000 Report of the AVMA Panel on Euthanasia. This is where the general guideline of a 20% CO2 replacement rate within one minute is found.

In the UK, there is the 2006 Newcastle Consensus Meeting on Carbon Dioxide Euthanasia of Laboratory Animals It's helpfully discussed and summarized here.

From the "Summary consensus points":
Problems with CO2 killing

1. There is no “ideal” way of killing animals with CO2 - both pre-fill and rising concentrations can cause welfare problems.

2. If animals are placed into a chamber containing a high concentration of CO2 (above 50 %), they will experience at least 10 to 15 seconds of pain in the mucosa of the upper airways before the loss of consciousness. This is a serious welfare problem.

3. If animals are placed into a chamber with a rising concentration of CO2, they will find it aversive at a certain level and may experience “air hunger” or dyspnoea, which is unpleasant (and, in humans, is reported as highly distressing). This may also be a serious welfare problem.
Here is a comprehensive review:
Carbon dioxide for euthanasia: concerns regarding pain and distress, with special reference to mice and rats
Lab Anim April 1, 2005 vol. 39 no. 2 137-161
I don't think that a gradually increasing level of CO2 is dangerous to humans because it will supposedly avoid the dyspnea reflex; rather, it's dangerous because unconsciousness and lethal CO2 poisoning of humans is possible at relatively low levels of CO2 concentrations, as described previously. It's a short distance from dyspnea to unconsciousness and death.
posted by Ivan Fyodorovich at 1:54 PM on January 21


If you have any citations for your claim that gradually raising CO2 levels avoids the dyspnea response, shelleycat, please provide them. "I have experience with this" doesn't count for much. You can search the research as well or better than I can, it shouldn't be too difficult if you're correct.
posted by Ivan Fyodorovich at 12:02 PM on January 22


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